I've seen similar, where people have lathered layer upon layer of packaging/duck tape on the back
in a vain attempt to keep the critters out. Alas! Little do they know. The flies go in the front. They
never go in from the back.

drpeej wrote:I got a call from a lady who asked if I could clean a 'few' thunder bugs out of a framed picture...
...The back revealed the cause of the problem...

drpeej wrote:I think in this case the back door was so wide open they just walked in en mass

Thunder flies or thrips do get in from the front of the frame so unless you seal up the glass package they will most likely get in again If you haven't used this method before here is a video showing how it is done https://www.youtube.com/watch?v=fk30bmLwQ2o Just use the P-90 tape no need for the foil method.

"You know, there's a right and wrong way to do everything!"Oliver Hardy.

For protection against thrips the foil method isn't necessary. I always use P-90 but some folk like to use masking tape or even sellotape I seal most of my work as it makes for a neat way of working... you can deal with the flumbs more easily as you are placing the glass on top of the art and not the art on top of the glass and then turning the frame over to check for flumbs

Flumb'Foreign object found under glass after sealing frame back.
Researchers have concluded that in their native state, flumbs are transparent. Through a process not well understood, these invisible pieces of debris become visible only after the frame has been completely assembled i.e. the art package (most frequently with mount board and glazing material) has been secured into the frame, the frame sealed with backing tape or a dust cover, and the hanging hardware applied. Without such processes, flumbs resist metamorphosis and remain unseen.
Under these ideal conditions flumbs transform into one of two visible states: white debris become visible when in contact with dark surfaces; while dark debris become visible when in contact with light surfaces. Some scientists postulate that this process may be a reverse phototropic phenomenon while other suggest that flumbs appear because of some transient, dimensional shifting, “worm hole” event.
Investigators continue to study these occurrences.'

"You know, there's a right and wrong way to do everything!"Oliver Hardy.

David McCormack wrote: as it makes for a neat way of working... you can deal with the flumbs more easily as you are placing the glass on top of the art and not the art on top of the glass and then turning the frame over to check for flumbs

You don't have to seal the package in order to assemble it the correct - face up - way.

I confess I can't see that. I am not aware that I have any difficulty in handling an un-taped-up frame and really can't see how faffing with tape would make it measurably easier. All I can think about is the fuss of untaping the package when you find a flumb after you've finished assembling the frame!

I only seal when using a dark mount (most time I don't, I like to walk on the wild side ) rest of the time I don't
Get work in regularly, reglaze broken glass in frames, if it's been done by a another local framer, I know I will have trouble, as the customer has tried to take the broken glass out of the frame from the front, but can't as it's Bl**dy taped in, so now have a frame that looks like an explosion ( ) has blown the front of the glass out, so now have shards of glass sticking out front, can't lay the frame face down to take it all apart
If I was on the framing committee, I would be working to get this method banned , anybody caught using it, drummed out of the trade

I'd also ban the use of self- adhesive tape on the back of frames! When the glass breaks, little shards of glass stick to this tape which makes it tricky to remove from the back of the frame without cutting yourself.

I have to admit that I hate the glass/picture/board/tape sandwich and have done it myself only once or twice if the job needed it for whatever reason.

I once had to replace smashed glass on a 100cm x 80cm poster that had been taped together. Not at all easy getting that apart on my own without damaging the poster! If I remember rightly it was Sellotape that had been used and it kept coming off in little bits.

I once had a nice landscape painting where a bug had got in and expired right in the sky.
They never go in the grass. Always in a prominent place right in your eyeline. It was a PITA
to remove the stain left and almost ruined the painting. Which was a big one.

After that I would consider slicing the internal sealing tape a minor inconvenience.

And if the glass breaks in neat chunks rather than a shatter the tape holds the shards in place
thus preventing further possible grief.